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<div class="titlepage"><div><div><h3 class="title">
<a name="boost_regex.ref.regex_iterator"></a><a class="link" href="regex_iterator.html" title="regex_iterator">regex_iterator</a>
</h3></div></div></div>
<p>
        The iterator type <a class="link" href="regex_iterator.html" title="regex_iterator"><code class="computeroutput"><span class="identifier">regex_iterator</span></code></a> will enumerate all
        of the regular expression matches found in some sequence: dereferencing a
        <a class="link" href="regex_iterator.html" title="regex_iterator"><code class="computeroutput"><span class="identifier">regex_iterator</span></code></a>
        yields a reference to a <a class="link" href="match_results.html" title="match_results"><code class="computeroutput"><span class="identifier">match_results</span></code></a> object.
      </p>
<pre class="programlisting"><span class="keyword">template</span> <span class="special">&lt;</span><span class="keyword">class</span> <span class="identifier">BidirectionalIterator</span><span class="special">,</span>
         <span class="keyword">class</span> <span class="identifier">charT</span> <span class="special">=</span> <span class="identifier">iterator_traits</span><span class="special">&lt;</span><span class="identifier">BidirectionalIterator</span><span class="special">&gt;::</span><span class="identifier">value_type</span><span class="special">,</span>
         <span class="keyword">class</span> <span class="identifier">traits</span> <span class="special">=</span> <span class="identifier">regex_traits</span><span class="special">&lt;</span><span class="identifier">charT</span><span class="special">&gt;</span> <span class="special">&gt;</span>
<span class="keyword">class</span> <span class="identifier">regex_iterator</span>
<span class="special">{</span>
<span class="keyword">public</span><span class="special">:</span>
   <span class="keyword">typedef</span>          <span class="identifier">basic_regex</span><span class="special">&lt;</span><span class="identifier">charT</span><span class="special">,</span> <span class="identifier">traits</span><span class="special">&gt;</span>                              <span class="identifier">regex_type</span><span class="special">;</span>
   <span class="keyword">typedef</span>          <span class="identifier">match_results</span><span class="special">&lt;</span><span class="identifier">BidirectionalIterator</span><span class="special">&gt;</span>                    <span class="identifier">value_type</span><span class="special">;</span>
   <span class="keyword">typedef</span> <span class="keyword">typename</span> <span class="identifier">iterator_traits</span><span class="special">&lt;</span><span class="identifier">BidirectionalIterator</span><span class="special">&gt;::</span><span class="identifier">difference_type</span> <span class="identifier">difference_type</span><span class="special">;</span>
   <span class="keyword">typedef</span>          <span class="keyword">const</span> <span class="identifier">value_type</span><span class="special">*</span>                                       <span class="identifier">pointer</span><span class="special">;</span>
   <span class="keyword">typedef</span>          <span class="keyword">const</span> <span class="identifier">value_type</span><span class="special">&amp;</span>                                       <span class="identifier">reference</span><span class="special">;</span>
   <span class="keyword">typedef</span>          <span class="identifier">std</span><span class="special">::</span><span class="identifier">forward_iterator_tag</span>                               <span class="identifier">iterator_category</span><span class="special">;</span>

   <a class="link" href="regex_iterator.html#boost_regex.regex_iterator.construct1">regex_iterator</a><span class="special">();</span>
   <a class="link" href="regex_iterator.html#boost_regex.regex_iterator.construct2">regex_iterator</a><span class="special">(</span><span class="identifier">BidirectionalIterator</span> <span class="identifier">a</span><span class="special">,</span> <span class="identifier">BidirectionalIterator</span> <span class="identifier">b</span><span class="special">,</span>
                  <span class="keyword">const</span> <span class="identifier">regex_type</span><span class="special">&amp;</span> <span class="identifier">re</span><span class="special">,</span>
                  <span class="identifier">match_flag_type</span> <span class="identifier">m</span> <span class="special">=</span> <span class="identifier">match_default</span><span class="special">);</span>
   <a class="link" href="regex_iterator.html#boost_regex.regex_iterator.construct3">regex_iterator</a><span class="special">(</span><span class="keyword">const</span> <span class="identifier">regex_iterator</span><span class="special">&amp;);</span>
   <span class="identifier">regex_iterator</span><span class="special">&amp;</span> <a class="link" href="regex_iterator.html#boost_regex.regex_iterator.assign">operator=(</a><span class="keyword">const</span> <span class="identifier">regex_iterator</span><span class="special">&amp;);</span>
   <span class="keyword">bool</span> <a class="link" href="regex_iterator.html#boost_regex.regex_iterator.op_eq">operator==</a><span class="special">(</span><span class="keyword">const</span> <span class="identifier">regex_iterator</span><span class="special">&amp;)</span><span class="keyword">const</span><span class="special">;</span>
   <span class="keyword">bool</span> <a class="link" href="regex_iterator.html#boost_regex.regex_iterator.op_ne">operator!=</a><span class="special">(</span><span class="keyword">const</span> <span class="identifier">regex_iterator</span><span class="special">&amp;)</span><span class="keyword">const</span><span class="special">;</span>
   <span class="keyword">const</span> <span class="identifier">value_type</span><span class="special">&amp;</span> <a class="link" href="regex_iterator.html#boost_regex.regex_iterator.op_deref">operator*</a><span class="special">()</span><span class="keyword">const</span><span class="special">;</span>
   <span class="keyword">const</span> <span class="identifier">value_type</span><span class="special">*</span> <a class="link" href="regex_iterator.html#boost_regex.regex_iterator.op_arrow">operator-&gt;</a><span class="special">()</span><span class="keyword">const</span><span class="special">;</span>
   <span class="identifier">regex_iterator</span><span class="special">&amp;</span> <a class="link" href="regex_iterator.html#boost_regex.regex_iterator.op_inc">operator++</a><span class="special">();</span>
   <span class="identifier">regex_iterator</span> <a class="link" href="regex_iterator.html#boost_regex.regex_iterator.op_inc2">operator++</a><span class="special">(</span><span class="keyword">int</span><span class="special">);</span>
<span class="special">};</span>

<span class="keyword">typedef</span> <span class="identifier">regex_iterator</span><span class="special">&lt;</span><span class="keyword">const</span> <span class="keyword">char</span><span class="special">*&gt;</span>                  <span class="identifier">cregex_iterator</span><span class="special">;</span>
<span class="keyword">typedef</span> <span class="identifier">regex_iterator</span><span class="special">&lt;</span><span class="identifier">std</span><span class="special">::</span><span class="identifier">string</span><span class="special">::</span><span class="identifier">const_iterator</span><span class="special">&gt;</span>  <span class="identifier">sregex_iterator</span><span class="special">;</span>

<span class="preprocessor">#ifndef</span>  <span class="identifier">BOOST_NO_WREGEX</span>
<span class="keyword">typedef</span> <span class="identifier">regex_iterator</span><span class="special">&lt;</span><span class="keyword">const</span> <span class="keyword">wchar_t</span><span class="special">*&gt;</span>               <span class="identifier">wcregex_iterator</span><span class="special">;</span>
<span class="keyword">typedef</span> <span class="identifier">regex_iterator</span><span class="special">&lt;</span><span class="identifier">std</span><span class="special">::</span><span class="identifier">wstring</span><span class="special">::</span><span class="identifier">const_iterator</span><span class="special">&gt;</span> <span class="identifier">wsregex_iterator</span><span class="special">;</span>
<span class="preprocessor">#endif</span>

<span class="keyword">template</span> <span class="special">&lt;</span><span class="keyword">class</span> <span class="identifier">charT</span><span class="special">,</span> <span class="keyword">class</span> <span class="identifier">traits</span><span class="special">&gt;</span> <span class="identifier">regex_iterator</span><span class="special">&lt;</span><span class="keyword">const</span> <span class="identifier">charT</span><span class="special">*,</span> <span class="identifier">charT</span><span class="special">,</span> <span class="identifier">traits</span><span class="special">&gt;</span>
   <a class="link" href="regex_iterator.html#boost_regex.regex_iterator.make">make_regex_iterator</a><span class="special">(</span><span class="keyword">const</span> <span class="identifier">charT</span><span class="special">*</span> <span class="identifier">p</span><span class="special">,</span> <span class="keyword">const</span> <span class="identifier">basic_regex</span><span class="special">&lt;</span><span class="identifier">charT</span><span class="special">,</span> <span class="identifier">traits</span><span class="special">&gt;&amp;</span> <span class="identifier">e</span><span class="special">,</span>
                       <span class="identifier">regex_constants</span><span class="special">::</span><span class="identifier">match_flag_type</span> <span class="identifier">m</span> <span class="special">=</span> <span class="identifier">regex_constants</span><span class="special">::</span><span class="identifier">match_default</span><span class="special">);</span>

<span class="keyword">template</span> <span class="special">&lt;</span><span class="keyword">class</span> <span class="identifier">charT</span><span class="special">,</span> <span class="keyword">class</span> <span class="identifier">traits</span><span class="special">,</span> <span class="keyword">class</span> <span class="identifier">ST</span><span class="special">,</span> <span class="keyword">class</span> <span class="identifier">SA</span><span class="special">&gt;</span>
   <span class="identifier">regex_iterator</span><span class="special">&lt;</span><span class="keyword">typename</span> <span class="identifier">std</span><span class="special">::</span><span class="identifier">basic_string</span><span class="special">&lt;</span><span class="identifier">charT</span><span class="special">,</span> <span class="identifier">ST</span><span class="special">,</span> <span class="identifier">SA</span><span class="special">&gt;::</span><span class="identifier">const_iterator</span><span class="special">,</span> <span class="identifier">charT</span><span class="special">,</span> <span class="identifier">traits</span><span class="special">&gt;</span>
      <a class="link" href="regex_iterator.html#boost_regex.regex_iterator.make">make_regex_iterator</a><span class="special">(</span><span class="keyword">const</span> <span class="identifier">std</span><span class="special">::</span><span class="identifier">basic_string</span><span class="special">&lt;</span><span class="identifier">charT</span><span class="special">,</span> <span class="identifier">ST</span><span class="special">,</span> <span class="identifier">SA</span><span class="special">&gt;&amp;</span> <span class="identifier">p</span><span class="special">,</span>
                          <span class="keyword">const</span> <span class="identifier">basic_regex</span><span class="special">&lt;</span><span class="identifier">charT</span><span class="special">,</span> <span class="identifier">traits</span><span class="special">&gt;&amp;</span> <span class="identifier">e</span><span class="special">,</span>
                          <span class="identifier">regex_constants</span><span class="special">::</span><span class="identifier">match_flag_type</span> <span class="identifier">m</span> <span class="special">=</span> <span class="identifier">regex_constants</span><span class="special">::</span><span class="identifier">match_default</span><span class="special">);</span>
</pre>
<h5>
<a name="boost_regex.ref.regex_iterator.h0"></a>
        <span class="phrase"><a name="boost_regex.ref.regex_iterator.description"></a></span><a class="link" href="regex_iterator.html#boost_regex.ref.regex_iterator.description">Description</a>
      </h5>
<p>
        A <a class="link" href="regex_iterator.html" title="regex_iterator"><code class="computeroutput"><span class="identifier">regex_iterator</span></code></a>
        is constructed from a pair of iterators, and enumerates all occurrences of
        a regular expression within that iterator range.
      </p>
<a name="boost_regex.regex_iterator.construct1"></a><pre class="programlisting"><span class="identifier">regex_iterator</span><span class="special">();</span>
</pre>
<p>
        <span class="bold"><strong>Effects</strong></span>: constructs an end of sequence
        <a class="link" href="regex_iterator.html" title="regex_iterator"><code class="computeroutput"><span class="identifier">regex_iterator</span></code></a>.
      </p>
<a name="boost_regex.regex_iterator.construct2"></a><pre class="programlisting"><span class="identifier">regex_iterator</span><span class="special">(</span><span class="identifier">BidirectionalIterator</span> <span class="identifier">a</span><span class="special">,</span> <span class="identifier">BidirectionalIterator</span> <span class="identifier">b</span><span class="special">,</span>
               <span class="keyword">const</span> <span class="identifier">regex_type</span><span class="special">&amp;</span> <span class="identifier">re</span><span class="special">,</span>
               <span class="identifier">match_flag_type</span> <span class="identifier">m</span> <span class="special">=</span> <span class="identifier">match_default</span><span class="special">);</span>
</pre>
<p>
        <span class="bold"><strong>Effects</strong></span>: constructs a <a class="link" href="regex_iterator.html" title="regex_iterator"><code class="computeroutput"><span class="identifier">regex_iterator</span></code></a> that will enumerate
        all occurrences of the expression <span class="emphasis"><em>re</em></span>, within the sequence
        [a,b), and found using <a class="link" href="match_flag_type.html" title="match_flag_type"><code class="computeroutput"><span class="identifier">match_flag_type</span></code></a> <span class="emphasis"><em>m</em></span>.
        The object <span class="emphasis"><em>re</em></span> must exist for the lifetime of the <a class="link" href="regex_iterator.html" title="regex_iterator"><code class="computeroutput"><span class="identifier">regex_iterator</span></code></a>.
      </p>
<p>
        <span class="bold"><strong>Throws</strong></span>: <code class="computeroutput"><span class="identifier">std</span><span class="special">::</span><span class="identifier">runtime_error</span></code>
        if the complexity of matching the expression against an N character string
        begins to exceed O(N<sup>2</sup>), or if the program runs out of stack space while matching
        the expression (if Boost.Regex is configured in recursive mode), or if the
        matcher exhausts its permitted memory allocation (if Boost.Regex is configured
        in non-recursive mode).
      </p>
<a name="boost_regex.regex_iterator.construct3"></a><pre class="programlisting"><span class="identifier">regex_iterator</span><span class="special">(</span><span class="keyword">const</span> <span class="identifier">regex_iterator</span><span class="special">&amp;</span> <span class="identifier">that</span><span class="special">);</span>
</pre>
<p>
        <span class="bold"><strong>Effects</strong></span>: constructs a copy of <code class="computeroutput"><span class="identifier">that</span></code>.
      </p>
<p>
        <span class="bold"><strong>Postconditions</strong></span>: <code class="computeroutput"><span class="special">*</span><span class="keyword">this</span> <span class="special">==</span> <span class="identifier">that</span></code>.
      </p>
<a name="boost_regex.regex_iterator.assign"></a><pre class="programlisting"><span class="identifier">regex_iterator</span><span class="special">&amp;</span> <span class="keyword">operator</span><span class="special">=(</span><span class="keyword">const</span> <span class="identifier">regex_iterator</span><span class="special">&amp;);</span>
</pre>
<p>
        <span class="bold"><strong>Effects</strong></span>: sets <code class="computeroutput"><span class="special">*</span><span class="keyword">this</span></code> equal to those in <code class="computeroutput"><span class="identifier">that</span></code>.
      </p>
<p>
        <span class="bold"><strong>Postconditions</strong></span>: *this == that.
      </p>
<a name="boost_regex.regex_iterator.op_eq"></a><pre class="programlisting"><span class="keyword">bool</span> <span class="keyword">operator</span><span class="special">==(</span><span class="keyword">const</span> <span class="identifier">regex_iterator</span><span class="special">&amp;</span> <span class="identifier">that</span><span class="special">)</span><span class="keyword">const</span><span class="special">;</span>
</pre>
<p>
        <span class="bold"><strong>Effects</strong></span>: returns true if *this is equal
        to that.
      </p>
<a name="boost_regex.regex_iterator.op_ne"></a><pre class="programlisting"><span class="keyword">bool</span> <span class="keyword">operator</span><span class="special">!=(</span><span class="keyword">const</span> <span class="identifier">regex_iterator</span><span class="special">&amp;)</span><span class="keyword">const</span><span class="special">;</span>
</pre>
<p>
        <span class="bold"><strong>Effects</strong></span>: returns <code class="computeroutput"><span class="special">!(*</span><span class="keyword">this</span> <span class="special">==</span> <span class="identifier">that</span><span class="special">)</span></code>.
      </p>
<a name="boost_regex.regex_iterator.op_deref"></a><pre class="programlisting"><span class="keyword">const</span> <span class="identifier">value_type</span><span class="special">&amp;</span> <span class="keyword">operator</span><span class="special">*()</span><span class="keyword">const</span><span class="special">;</span>
</pre>
<p>
        <span class="bold"><strong>Effects</strong></span>: dereferencing a <a class="link" href="regex_iterator.html" title="regex_iterator"><code class="computeroutput"><span class="identifier">regex_iterator</span></code></a> object it yields
        a const reference to a <a class="link" href="match_results.html" title="match_results"><code class="computeroutput"><span class="identifier">match_results</span></code></a> object, whose members
        are set as follows:
      </p>
<div class="informaltable"><table class="table">
<colgroup>
<col>
<col>
</colgroup>
<thead><tr>
<th>
                <p>
                  Element
                </p>
              </th>
<th>
                <p>
                  Value
                </p>
              </th>
</tr></thead>
<tbody>
<tr>
<td>
                <p>
                  <code class="computeroutput"><span class="special">(*</span><span class="identifier">it</span><span class="special">).</span><span class="identifier">size</span><span class="special">()</span></code>
                </p>
              </td>
<td>
                <p>
                  <code class="computeroutput"><span class="number">1</span> <span class="special">+</span>
                  <span class="identifier">re</span><span class="special">.</span><span class="identifier">mark_count</span><span class="special">()</span></code>
                </p>
              </td>
</tr>
<tr>
<td>
                <p>
                  <code class="computeroutput"><span class="special">(*</span><span class="identifier">it</span><span class="special">).</span><span class="identifier">empty</span><span class="special">()</span></code>
                </p>
              </td>
<td>
                <p>
                  <code class="computeroutput"><span class="keyword">false</span></code>
                </p>
              </td>
</tr>
<tr>
<td>
                <p>
                  <code class="computeroutput"><span class="special">(*</span><span class="identifier">it</span><span class="special">).</span><span class="identifier">prefix</span><span class="special">().</span><span class="identifier">first</span></code>
                </p>
              </td>
<td>
                <p>
                  The end of the last match found, or the start of the underlying
                  sequence if this is the first match enumerated
                </p>
              </td>
</tr>
<tr>
<td>
                <p>
                  <code class="computeroutput"><span class="special">(*</span><span class="identifier">it</span><span class="special">).</span><span class="identifier">prefix</span><span class="special">().</span><span class="identifier">second</span></code>
                </p>
              </td>
<td>
                <p>
                  The same as the start of the match found: <code class="computeroutput"><span class="special">(*</span><span class="identifier">it</span><span class="special">)[</span><span class="number">0</span><span class="special">].</span><span class="identifier">first</span></code>
                </p>
              </td>
</tr>
<tr>
<td>
                <p>
                  <code class="computeroutput"><span class="special">(*</span><span class="identifier">it</span><span class="special">).</span><span class="identifier">prefix</span><span class="special">().</span><span class="identifier">matched</span></code>
                </p>
              </td>
<td>
                <p>
                  True if the prefix did not match an empty string: <code class="computeroutput"><span class="special">(*</span><span class="identifier">it</span><span class="special">).</span><span class="identifier">prefix</span><span class="special">().</span><span class="identifier">first</span>
                  <span class="special">!=</span> <span class="special">(*</span><span class="identifier">it</span><span class="special">).</span><span class="identifier">prefix</span><span class="special">().</span><span class="identifier">second</span></code>
                </p>
              </td>
</tr>
<tr>
<td>
                <p>
                  <code class="computeroutput"><span class="special">(*</span><span class="identifier">it</span><span class="special">).</span><span class="identifier">suffix</span><span class="special">().</span><span class="identifier">first</span></code>
                </p>
              </td>
<td>
                <p>
                  The same as the end of the match found: <code class="computeroutput"><span class="special">(*</span><span class="identifier">it</span><span class="special">)[</span><span class="number">0</span><span class="special">].</span><span class="identifier">second</span></code>
                </p>
              </td>
</tr>
<tr>
<td>
                <p>
                  <code class="computeroutput"><span class="special">(*</span><span class="identifier">it</span><span class="special">).</span><span class="identifier">suffix</span><span class="special">().</span><span class="identifier">second</span></code>
                </p>
              </td>
<td>
                <p>
                  The end of the underlying sequence.
                </p>
              </td>
</tr>
<tr>
<td>
                <p>
                  <code class="computeroutput"><span class="special">(*</span><span class="identifier">it</span><span class="special">).</span><span class="identifier">suffix</span><span class="special">().</span><span class="identifier">matched</span></code>
                </p>
              </td>
<td>
                <p>
                  True if the suffix did not match an empty string: <code class="computeroutput"><span class="special">(*</span><span class="identifier">it</span><span class="special">).</span><span class="identifier">suffix</span><span class="special">().</span><span class="identifier">first</span>
                  <span class="special">!=</span> <span class="special">(*</span><span class="identifier">it</span><span class="special">).</span><span class="identifier">suffix</span><span class="special">().</span><span class="identifier">second</span></code>
                </p>
              </td>
</tr>
<tr>
<td>
                <p>
                  <code class="computeroutput"><span class="special">(*</span><span class="identifier">it</span><span class="special">)[</span><span class="number">0</span><span class="special">].</span><span class="identifier">first</span></code>
                </p>
              </td>
<td>
                <p>
                  The start of the sequence of characters that matched the regular
                  expression
                </p>
              </td>
</tr>
<tr>
<td>
                <p>
                  <code class="computeroutput"><span class="special">(*</span><span class="identifier">it</span><span class="special">)[</span><span class="number">0</span><span class="special">].</span><span class="identifier">second</span></code>
                </p>
              </td>
<td>
                <p>
                  The end of the sequence of characters that matched the regular
                  expression
                </p>
              </td>
</tr>
<tr>
<td>
                <p>
                  <code class="computeroutput"><span class="special">(*</span><span class="identifier">it</span><span class="special">)[</span><span class="number">0</span><span class="special">].</span><span class="identifier">matched</span></code>
                </p>
              </td>
<td>
                <p>
                  true if a full match was found, and false if it was a partial match
                  (found as a result of the match_partial flag being set).
                </p>
              </td>
</tr>
<tr>
<td>
                <p>
                  <code class="computeroutput"><span class="special">(*</span><span class="identifier">it</span><span class="special">)[</span><span class="identifier">n</span><span class="special">].</span><span class="identifier">first</span></code>
                </p>
              </td>
<td>
                <p>
                  For all integers <code class="computeroutput"><span class="identifier">n</span> <span class="special">&lt;</span> <span class="special">(*</span><span class="identifier">it</span><span class="special">).</span><span class="identifier">size</span><span class="special">()</span></code>,
                  the start of the sequence that matched sub-expression <span class="emphasis"><em>n</em></span>.
                  Alternatively, if sub-expression <span class="emphasis"><em>n</em></span> did not
                  participate in the match, then last.
                </p>
              </td>
</tr>
<tr>
<td>
                <p>
                  <code class="computeroutput"><span class="special">(*</span><span class="identifier">it</span><span class="special">)[</span><span class="identifier">n</span><span class="special">].</span><span class="identifier">second</span></code>
                </p>
              </td>
<td>
                <p>
                  For all integers <code class="computeroutput"><span class="identifier">n</span> <span class="special">&lt;</span> <span class="special">(*</span><span class="identifier">it</span><span class="special">).</span><span class="identifier">size</span><span class="special">()</span></code>,
                  the end of the sequence that matched sub-expression <span class="emphasis"><em>n</em></span>.
                  Alternatively, if sub-expression <span class="emphasis"><em>n</em></span> did not
                  participate in the match, then last.
                </p>
              </td>
</tr>
<tr>
<td>
                <p>
                  <code class="computeroutput"><span class="special">(*</span><span class="identifier">it</span><span class="special">)[</span><span class="identifier">n</span><span class="special">].</span><span class="identifier">matched</span></code>
                </p>
              </td>
<td>
                <p>
                  For all integers <code class="computeroutput"><span class="identifier">n</span> <span class="special">&lt;</span> <span class="special">(*</span><span class="identifier">it</span><span class="special">).</span><span class="identifier">size</span><span class="special">()</span></code>,
                  true if sub-expression <span class="emphasis"><em>n</em></span> participated in the
                  match, false otherwise.
                </p>
              </td>
</tr>
<tr>
<td>
                <p>
                  <code class="computeroutput"><span class="special">(*</span><span class="identifier">it</span><span class="special">).</span><span class="identifier">position</span><span class="special">(</span><span class="identifier">n</span><span class="special">)</span></code>
                </p>
              </td>
<td>
                <p>
                  For all integers <code class="computeroutput"><span class="identifier">n</span> <span class="special">&lt;</span> <span class="special">(*</span><span class="identifier">it</span><span class="special">).</span><span class="identifier">size</span><span class="special">()</span></code>,
                  then the distance from the start of the underlying sequence to
                  the start of sub-expression match <span class="emphasis"><em>n</em></span>.
                </p>
              </td>
</tr>
</tbody>
</table></div>
<a name="boost_regex.regex_iterator.op_arrow"></a><pre class="programlisting"><span class="keyword">const</span> <span class="identifier">value_type</span><span class="special">*</span> <span class="keyword">operator</span><span class="special">-&gt;()</span><span class="keyword">const</span><span class="special">;</span>
</pre>
<p>
        <span class="bold"><strong>Effects</strong></span>: returns <code class="computeroutput"><span class="special">&amp;(*</span><span class="keyword">this</span><span class="special">)</span></code>.
      </p>
<a name="boost_regex.regex_iterator.op_inc"></a><pre class="programlisting"><span class="identifier">regex_iterator</span><span class="special">&amp;</span> <span class="keyword">operator</span><span class="special">++();</span>
</pre>
<p>
        <span class="bold"><strong>Effects</strong></span>: moves the iterator to the next
        match in the underlying sequence, or the end of sequence iterator if none
        if found. When the last match found matched a zero length string, then the
        <a class="link" href="regex_iterator.html" title="regex_iterator"><code class="computeroutput"><span class="identifier">regex_iterator</span></code></a>
        will find the next match as follows: if there exists a non-zero length match
        that starts at the same location as the last one, then returns it, otherwise
        starts looking for the next (possibly zero length) match from one position
        to the right of the last match.
      </p>
<p>
        <span class="bold"><strong>Throws</strong></span>: <code class="computeroutput"><span class="identifier">std</span><span class="special">::</span><span class="identifier">runtime_error</span></code>
        if the complexity of matching the expression against an N character string
        begins to exceed O(N<sup>2</sup>), or if the program runs out of stack space while matching
        the expression (if Boost.Regex is configured in recursive mode), or if the
        matcher exhausts its permitted memory allocation (if Boost.Regex is configured
        in non-recursive mode).
      </p>
<p>
        <span class="bold"><strong>Returns</strong></span>: *this.
      </p>
<a name="boost_regex.regex_iterator.op_inc2"></a><pre class="programlisting"><span class="identifier">regex_iterator</span> <span class="keyword">operator</span><span class="special">++(</span><span class="keyword">int</span><span class="special">);</span>
</pre>
<p>
        <span class="bold"><strong>Effects</strong></span>: constructs a copy result of <code class="computeroutput"><span class="special">*</span><span class="keyword">this</span></code>, then
        calls <code class="computeroutput"><span class="special">++(*</span><span class="keyword">this</span><span class="special">)</span></code>.
      </p>
<p>
        <span class="bold"><strong>Returns</strong></span>: result.
      </p>
<a name="boost_regex.regex_iterator.make"></a><pre class="programlisting"><span class="keyword">template</span> <span class="special">&lt;</span><span class="keyword">class</span> <span class="identifier">charT</span><span class="special">,</span> <span class="keyword">class</span> <span class="identifier">traits</span><span class="special">&gt;</span>
<span class="identifier">regex_iterator</span><span class="special">&lt;</span><span class="keyword">const</span> <span class="identifier">charT</span><span class="special">*,</span> <span class="identifier">charT</span><span class="special">,</span> <span class="identifier">traits</span><span class="special">&gt;</span>
   <span class="identifier">make_regex_iterator</span><span class="special">(</span><span class="keyword">const</span> <span class="identifier">charT</span><span class="special">*</span> <span class="identifier">p</span><span class="special">,</span> <span class="keyword">const</span> <span class="identifier">basic_regex</span><span class="special">&lt;</span><span class="identifier">charT</span><span class="special">,</span> <span class="identifier">traits</span><span class="special">&gt;&amp;</span> <span class="identifier">e</span><span class="special">,</span>
                     <span class="identifier">regex_constants</span><span class="special">::</span><span class="identifier">match_flag_type</span> <span class="identifier">m</span> <span class="special">=</span> <span class="identifier">regex_constants</span><span class="special">::</span><span class="identifier">match_default</span><span class="special">);</span>

<span class="keyword">template</span> <span class="special">&lt;</span><span class="keyword">class</span> <span class="identifier">charT</span><span class="special">,</span> <span class="keyword">class</span> <span class="identifier">traits</span><span class="special">,</span> <span class="keyword">class</span> <span class="identifier">ST</span><span class="special">,</span> <span class="keyword">class</span> <span class="identifier">SA</span><span class="special">&gt;</span>
<span class="identifier">regex_iterator</span><span class="special">&lt;</span><span class="keyword">typename</span> <span class="identifier">std</span><span class="special">::</span><span class="identifier">basic_string</span><span class="special">&lt;</span><span class="identifier">charT</span><span class="special">,</span> <span class="identifier">ST</span><span class="special">,</span> <span class="identifier">SA</span><span class="special">&gt;::</span><span class="identifier">const_iterator</span><span class="special">,</span> <span class="identifier">charT</span><span class="special">,</span> <span class="identifier">traits</span><span class="special">&gt;</span>
   <span class="identifier">make_regex_iterator</span><span class="special">(</span><span class="keyword">const</span> <span class="identifier">std</span><span class="special">::</span><span class="identifier">basic_string</span><span class="special">&lt;</span><span class="identifier">charT</span><span class="special">,</span> <span class="identifier">ST</span><span class="special">,</span> <span class="identifier">SA</span><span class="special">&gt;&amp;</span> <span class="identifier">p</span><span class="special">,</span>
                     <span class="keyword">const</span> <span class="identifier">basic_regex</span><span class="special">&lt;</span><span class="identifier">charT</span><span class="special">,</span> <span class="identifier">traits</span><span class="special">&gt;&amp;</span> <span class="identifier">e</span><span class="special">,</span>
                     <span class="identifier">regex_constants</span><span class="special">::</span><span class="identifier">match_flag_type</span> <span class="identifier">m</span> <span class="special">=</span> <span class="identifier">regex_constants</span><span class="special">::</span><span class="identifier">match_default</span><span class="special">);</span>
</pre>
<p>
        <span class="bold"><strong>Effects</strong></span>: returns an iterator that enumerates
        all occurrences of expression <span class="emphasis"><em>e</em></span> in text <span class="emphasis"><em>p</em></span>
        using <a class="link" href="match_flag_type.html" title="match_flag_type"><code class="computeroutput"><span class="identifier">match_flag_type</span></code></a>
        <span class="emphasis"><em>m</em></span>.
      </p>
<h5>
<a name="boost_regex.ref.regex_iterator.h1"></a>
        <span class="phrase"><a name="boost_regex.ref.regex_iterator.examples"></a></span><a class="link" href="regex_iterator.html#boost_regex.ref.regex_iterator.examples">Examples</a>
      </h5>
<p>
        The following example takes a C++ source file and builds up an index of class
        names, and the location of that class in the file.
      </p>
<pre class="programlisting"><span class="preprocessor">#include</span> <span class="special">&lt;</span><span class="identifier">string</span><span class="special">&gt;</span>
<span class="preprocessor">#include</span> <span class="special">&lt;</span><span class="identifier">map</span><span class="special">&gt;</span>
<span class="preprocessor">#include</span> <span class="special">&lt;</span><span class="identifier">fstream</span><span class="special">&gt;</span>
<span class="preprocessor">#include</span> <span class="special">&lt;</span><span class="identifier">iostream</span><span class="special">&gt;</span>
<span class="preprocessor">#include</span> <span class="special">&lt;</span><span class="identifier">boost</span><span class="special">/</span><span class="identifier">regex</span><span class="special">.</span><span class="identifier">hpp</span><span class="special">&gt;</span>

<span class="keyword">using</span> <span class="keyword">namespace</span> <span class="identifier">std</span><span class="special">;</span>

<span class="comment">// purpose:</span>
<span class="comment">// takes the contents of a file in the form of a string</span>
<span class="comment">// and searches for all the C++ class definitions, storing</span>
<span class="comment">// their locations in a map of strings/int's</span>

<span class="keyword">typedef</span> <span class="identifier">std</span><span class="special">::</span><span class="identifier">map</span><span class="special">&lt;</span><span class="identifier">std</span><span class="special">::</span><span class="identifier">string</span><span class="special">,</span> <span class="identifier">std</span><span class="special">::</span><span class="identifier">string</span><span class="special">::</span><span class="identifier">difference_type</span><span class="special">,</span> <span class="identifier">std</span><span class="special">::</span><span class="identifier">less</span><span class="special">&lt;</span><span class="identifier">std</span><span class="special">::</span><span class="identifier">string</span><span class="special">&gt;</span> <span class="special">&gt;</span> <span class="identifier">map_type</span><span class="special">;</span>

<span class="keyword">const</span> <span class="keyword">char</span><span class="special">*</span> <span class="identifier">re</span> <span class="special">=</span>
   <span class="comment">// possibly leading whitespace:   </span>
   <span class="string">"^[[:space:]]*"</span>
   <span class="comment">// possible template declaration:</span>
   <span class="string">"(template[[:space:]]*&lt;[^;:{]+&gt;[[:space:]]*)?"</span>
   <span class="comment">// class or struct:</span>
   <span class="string">"(class|struct)[[:space:]]*"</span>
   <span class="comment">// leading declspec macros etc:</span>
   <span class="string">"("</span>
      <span class="string">"\\&lt;\\w+\\&gt;"</span>
      <span class="string">"("</span>
         <span class="string">"[[:blank:]]*\\([^)]*\\)"</span>
      <span class="string">")?"</span>
      <span class="string">"[[:space:]]*"</span>
   <span class="string">")*"</span>
   <span class="comment">// the class name</span>
   <span class="string">"(\\&lt;\\w*\\&gt;)[[:space:]]*"</span>
   <span class="comment">// template specialisation parameters</span>
   <span class="string">"(&lt;[^;:{]+&gt;)?[[:space:]]*"</span>
   <span class="comment">// terminate in { or :</span>
   <span class="string">"(\\{|:[^;\\{()]*\\{)"</span><span class="special">;</span>


<span class="identifier">boost</span><span class="special">::</span><span class="identifier">regex</span> <span class="identifier">expression</span><span class="special">(</span><span class="identifier">re</span><span class="special">);</span>
<span class="identifier">map_type</span> <span class="identifier">class_index</span><span class="special">;</span>

<span class="keyword">bool</span> <span class="identifier">regex_callback</span><span class="special">(</span><span class="keyword">const</span> <span class="identifier">boost</span><span class="special">::</span><span class="identifier">match_results</span><span class="special">&lt;</span><span class="identifier">std</span><span class="special">::</span><span class="identifier">string</span><span class="special">::</span><span class="identifier">const_iterator</span><span class="special">&gt;&amp;</span> <span class="identifier">what</span><span class="special">)</span>
<span class="special">{</span>
   <span class="comment">// what[0] contains the whole string</span>
   <span class="comment">// what[5] contains the class name.</span>
   <span class="comment">// what[6] contains the template specialisation if any.</span>
   <span class="comment">// add class name and position to map:</span>
   <span class="identifier">class_index</span><span class="special">[</span><span class="identifier">what</span><span class="special">[</span><span class="number">5</span><span class="special">].</span><span class="identifier">str</span><span class="special">()</span> <span class="special">+</span> <span class="identifier">what</span><span class="special">[</span><span class="number">6</span><span class="special">].</span><span class="identifier">str</span><span class="special">()]</span> <span class="special">=</span> <span class="identifier">what</span><span class="special">.</span><span class="identifier">position</span><span class="special">(</span><span class="number">5</span><span class="special">);</span>
   <span class="keyword">return</span> <span class="keyword">true</span><span class="special">;</span>
<span class="special">}</span>

<span class="keyword">void</span> <span class="identifier">load_file</span><span class="special">(</span><span class="identifier">std</span><span class="special">::</span><span class="identifier">string</span><span class="special">&amp;</span> <span class="identifier">s</span><span class="special">,</span> <span class="identifier">std</span><span class="special">::</span><span class="identifier">istream</span><span class="special">&amp;</span> <span class="identifier">is</span><span class="special">)</span>
<span class="special">{</span>
   <span class="identifier">s</span><span class="special">.</span><span class="identifier">erase</span><span class="special">();</span>
   <span class="identifier">s</span><span class="special">.</span><span class="identifier">reserve</span><span class="special">(</span><span class="identifier">is</span><span class="special">.</span><span class="identifier">rdbuf</span><span class="special">()-&gt;</span><span class="identifier">in_avail</span><span class="special">());</span>
   <span class="keyword">char</span> <span class="identifier">c</span><span class="special">;</span>
   <span class="keyword">while</span><span class="special">(</span><span class="identifier">is</span><span class="special">.</span><span class="identifier">get</span><span class="special">(</span><span class="identifier">c</span><span class="special">))</span>
   <span class="special">{</span>
      <span class="keyword">if</span><span class="special">(</span><span class="identifier">s</span><span class="special">.</span><span class="identifier">capacity</span><span class="special">()</span> <span class="special">==</span> <span class="identifier">s</span><span class="special">.</span><span class="identifier">size</span><span class="special">())</span>
         <span class="identifier">s</span><span class="special">.</span><span class="identifier">reserve</span><span class="special">(</span><span class="identifier">s</span><span class="special">.</span><span class="identifier">capacity</span><span class="special">()</span> <span class="special">*</span> <span class="number">3</span><span class="special">);</span>
      <span class="identifier">s</span><span class="special">.</span><span class="identifier">append</span><span class="special">(</span><span class="number">1</span><span class="special">,</span> <span class="identifier">c</span><span class="special">);</span>
   <span class="special">}</span>
<span class="special">}</span>

<span class="keyword">int</span> <span class="identifier">main</span><span class="special">(</span><span class="keyword">int</span> <span class="identifier">argc</span><span class="special">,</span> <span class="keyword">const</span> <span class="keyword">char</span><span class="special">**</span> <span class="identifier">argv</span><span class="special">)</span>
<span class="special">{</span>
   <span class="identifier">std</span><span class="special">::</span><span class="identifier">string</span> <span class="identifier">text</span><span class="special">;</span>
   <span class="keyword">for</span><span class="special">(</span><span class="keyword">int</span> <span class="identifier">i</span> <span class="special">=</span> <span class="number">1</span><span class="special">;</span> <span class="identifier">i</span> <span class="special">&lt;</span> <span class="identifier">argc</span><span class="special">;</span> <span class="special">++</span><span class="identifier">i</span><span class="special">)</span>
   <span class="special">{</span>
      <span class="identifier">cout</span> <span class="special">&lt;&lt;</span> <span class="string">"Processing file "</span> <span class="special">&lt;&lt;</span> <span class="identifier">argv</span><span class="special">[</span><span class="identifier">i</span><span class="special">]</span> <span class="special">&lt;&lt;</span> <span class="identifier">endl</span><span class="special">;</span>
      <span class="identifier">std</span><span class="special">::</span><span class="identifier">ifstream</span> <span class="identifier">fs</span><span class="special">(</span><span class="identifier">argv</span><span class="special">[</span><span class="identifier">i</span><span class="special">]);</span>
      <span class="identifier">load_file</span><span class="special">(</span><span class="identifier">text</span><span class="special">,</span> <span class="identifier">fs</span><span class="special">);</span>
      <span class="comment">// construct our iterators:</span>
      <span class="identifier">boost</span><span class="special">::</span><span class="identifier">sregex_iterator</span> <span class="identifier">m1</span><span class="special">(</span><span class="identifier">text</span><span class="special">.</span><span class="identifier">begin</span><span class="special">(),</span> <span class="identifier">text</span><span class="special">.</span><span class="identifier">end</span><span class="special">(),</span> <span class="identifier">expression</span><span class="special">);</span>
      <span class="identifier">boost</span><span class="special">::</span><span class="identifier">sregex_iterator</span> <span class="identifier">m2</span><span class="special">;</span>
      <span class="identifier">std</span><span class="special">::</span><span class="identifier">for_each</span><span class="special">(</span><span class="identifier">m1</span><span class="special">,</span> <span class="identifier">m2</span><span class="special">,</span> <span class="special">&amp;</span><span class="identifier">regex_callback</span><span class="special">);</span>
      <span class="comment">// copy results:</span>
      <span class="identifier">cout</span> <span class="special">&lt;&lt;</span> <span class="identifier">class_index</span><span class="special">.</span><span class="identifier">size</span><span class="special">()</span> <span class="special">&lt;&lt;</span> <span class="string">" matches found"</span> <span class="special">&lt;&lt;</span> <span class="identifier">endl</span><span class="special">;</span>
      <span class="identifier">map_type</span><span class="special">::</span><span class="identifier">iterator</span> <span class="identifier">c</span><span class="special">,</span> <span class="identifier">d</span><span class="special">;</span>
      <span class="identifier">c</span> <span class="special">=</span> <span class="identifier">class_index</span><span class="special">.</span><span class="identifier">begin</span><span class="special">();</span>
      <span class="identifier">d</span> <span class="special">=</span> <span class="identifier">class_index</span><span class="special">.</span><span class="identifier">end</span><span class="special">();</span>
      <span class="keyword">while</span><span class="special">(</span><span class="identifier">c</span> <span class="special">!=</span> <span class="identifier">d</span><span class="special">)</span>
      <span class="special">{</span>
         <span class="identifier">cout</span> <span class="special">&lt;&lt;</span> <span class="string">"class \""</span> <span class="special">&lt;&lt;</span> <span class="special">(*</span><span class="identifier">c</span><span class="special">).</span><span class="identifier">first</span> <span class="special">&lt;&lt;</span> <span class="string">"\" found at index: "</span> <span class="special">&lt;&lt;</span> <span class="special">(*</span><span class="identifier">c</span><span class="special">).</span><span class="identifier">second</span> <span class="special">&lt;&lt;</span> <span class="identifier">endl</span><span class="special">;</span>
         <span class="special">++</span><span class="identifier">c</span><span class="special">;</span>
      <span class="special">}</span>
      <span class="identifier">class_index</span><span class="special">.</span><span class="identifier">erase</span><span class="special">(</span><span class="identifier">class_index</span><span class="special">.</span><span class="identifier">begin</span><span class="special">(),</span> <span class="identifier">class_index</span><span class="special">.</span><span class="identifier">end</span><span class="special">());</span>
   <span class="special">}</span>
   <span class="keyword">return</span> <span class="number">0</span><span class="special">;</span>
<span class="special">}</span>
</pre>
</div>
<table xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" width="100%"><tr>
<td align="left"></td>
<td align="right"><div class="copyright-footer">Copyright © 1998-2013 John Maddock<p>
        Distributed under the Boost Software License, Version 1.0. (See accompanying
        file LICENSE_1_0.txt or copy at <a href="http://www.boost.org/LICENSE_1_0.txt" target="_top">http://www.boost.org/LICENSE_1_0.txt</a>)
      </p>
</div></td>
</tr></table>
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